It's hard to compare the CHP-2500 to the likes of Sennheiser HD25-1 II as they have different sound signature. As TDS said, the HD25-1 II is a reference headphones aimed for an analytical sound while the CHP-2500 is a fun headphones.

BTW, the Beyerdynamic earpads are amazing. They don't change the SQ at all yet they are extremely comfortable.